Editing CubeSat (section)

==Design==

The CubeSat specification accomplishes several high-level goals. The main reason for miniaturizing satellites is to reduce the cost of deployment: they are often suitable for launch in multiples, using the excess capacity of larger launch vehicles. The CubeSat design specifically minimizes risk to the rest of the launch vehicle and payloads. Encapsulation of the launcher–[[Payload (air and space craft)|payload]] interface takes away the amount of work that would previously be required for mating a piggyback satellite with its launcher. Unification among payloads and launchers enables quick exchanges of payloads and utilization of launch opportunities on short notice.

Standard CubeSats are made up of {{cvt|10x10x11.35|cm}} units designed to provide {{cvt|10x10x10|cm}} or {{cvt|1|L}} of useful volume, with each unit weighing no more than {{Cvt|2|kg|lb}}.<ref name=":6" /> The smallest standard size is 1U, consisting of a single unit, while the most common form factor was the 3U, which comprised over 40% of all nanosatellites launched to date.<ref>{{Cite web |last=Kulu |first=Erik |title=Cubesat types |url=https://www.nanosats.eu/#figures |access-date=2022-04-12 |website=Nanosats Database}}</ref><ref name='specs'>{{Cite web| url = https://static1.squarespace.com/static/5418c831e4b0fa4ecac1bacd/t/56e9b62337013b6c063a655a/1458157095454/cds_rev13_final2.pdf |title = CubeSat Design Specification| date = February 20, 2014| access-date = March 25, 2017|website = The CubeSat Program, CalPoly SLO|last = Mehrparvar|first = Arash}}</ref> Larger form factors, such as the 6U and 12U, are composed of 3Us stacked side by side.<ref name=":6" /> In 2014, two 6U [[Perseus-M]] CubeSats were launched for maritime surveillance, the largest yet at the time. The [[Mars Cube One]] (MarCO) mission in 2018 launched two 6U cubesats towards Mars.<ref>{{Cite web |title=MarCO: Planetary CubeSats Become Real |url=http://www.planetary.org/blogs/guest-blogs/van-kane/0708-marco-planetary-cubesats.html |access-date=2016-02-23 |website=www.planetary.org}}</ref><ref>{{Cite web |last=Clark |first=Stephen |title=Launch of NASA's next Mars mission delayed until at least 2018 {{!}} Spaceflight Now |url=http://spaceflightnow.com/2015/12/27/launch-of-nasas-next-mars-mission-delayed-until-at-least-2018/ |access-date=2016-02-23}}</ref>

Smaller, non-standard form factors also exist; [[The Aerospace Corporation]] has constructed and launched two smaller form CubeSats of 0.5U for radiation measurement and technological demonstration,<ref>{{Cite web|title = AeroCube 6A, 6B (CubeRad A, B)|url = http://space.skyrocket.de/doc_sdat/aerocube-6.htm|website = space.skyrocket.de| access-date = 2015-10-18}}</ref> while [[Swarm Technologies]] has built and deployed a constellation of over one hundred 0.25U CubeSats for [[Internet of things|IoT]] communication services.<ref>{{Cite web |title=SpaceBEE 10, ..., 180 |url=https://space.skyrocket.de/doc_sdat/spacebee-10.htm |access-date=2022-04-12 |website=Gunter's Space Page}}</ref><ref>{{Cite web |title=Swarm gets green light from FCC for its 150-satellite constellation |url=https://techcrunch.com/2019/10/17/swarm-gets-green-light-from-fcc-for-its-150-satellite-constellation/ |access-date=2022-04-12 |website=TechCrunch |date=18 October 2019}}</ref> 

[[File:Scientist holding a CubeSat.jpg|thumb|Scientist holding a CubeSat chassis]]
Since nearly all CubeSats are {{cvt|10x10|cm}} (regardless of length) they can all be launched and deployed using a common deployment system called a Poly-PicoSatellite Orbital Deployer (P-POD), developed and built by Cal Poly.<ref name="esappod">{{cite web |title=Educational Payload on the Vega Maiden Flight – Call For CubeSat Proposals |url=http://esamultimedia.esa.int/docs/LEX-EC/CubeSat_CFP_issue_1_rev_1.pdf |year=2008 |publisher=[[European Space Agency]] |access-date=2008-12-07}}</ref>

No electronics [[Computer form factor|form factors]] or communications protocols are specified or required by the CubeSat Design Specification, but COTS hardware has consistently used certain features which many treat as standards in CubeSat electronics. Most COTS and custom designed electronics fit the form of [[PC/104]], which was not designed for CubeSats but presents a {{cvt|90x96|mm}} profile that allows most of the spacecraft's volume to be occupied. Technically, the PCI-104 form is the variant of PC/104 used<ref>{{Cite web|title = PCI/104-Express – PC/104 Consortium|url = http://pc104.org/hardware-specifications/pci104-express/|website = PC/104 Consortium|access-date = 2015-10-22}}</ref> and the actual [[pinout]] used does not reflect the pinout specified in the PCI-104 standard. Stackthrough connectors on the boards allow for simple assembly and electrical interfacing and most manufacturers of CubeSat electronics hardware hold to the same signal arrangement, but some products do not, so care must be taken to ensure consistent signal and power arrangements to prevent damage.<ref>{{Cite web| title=FAQ| url=http://www.cubesatshop.com/index.php?option=com_content&view=section&layout=blog&id=10&Itemid=82| website=www.cubesatshop.com| access-date=2015-10-22}}</ref>

Care must be taken in electronics selection to ensure the devices can tolerate the radiation present. For very [[low Earth orbit]]s (LEO) in which atmospheric reentry would occur in just days or weeks, [[radiation]] can largely be ignored and standard consumer grade electronics may be used. Consumer electronic devices can survive LEO radiation for that time as the chance of a [[single event upset]] (SEU) is very low. Spacecraft in a sustained low Earth orbit lasting months or years are at risk and only fly hardware designed for and tested in irradiated environments. Missions beyond low Earth orbit or which would remain in low Earth orbit for many years must use [[Radiation hardening|radiation-hardened]] devices.<ref>{{Cite web| title = Space Radiation Effects on Electronic Components in Low Earth Orbit| url = http://www.diyspaceexploration.com/space-radiation-effects-on-electronic-components-in-low-earth-orbit/| website = DIY Space Exploration| access-date = 2015-11-05| language = en-US| url-status = usurped| archive-url = https://web.archive.org/web/20151027221637/http://www.diyspaceexploration.com/space-radiation-effects-on-electronic-components-in-low-earth-orbit/| archive-date = 2015-10-27}}</ref> Further considerations are made for operation in high vacuum due to the effects of [[Sublimation (phase transition)|sublimation]], [[outgassing]], and [[Whisker (metallurgy)|metal whiskers]], which may result in mission failure.<ref>{{Cite web| url = http://nepp.nasa.gov/whisker/failures/| title = Whisker Failures| access-date = 2015-11-05| date = 2009-08-09| publisher = NASA}}</ref>

===Structure===

The number of joined units classifies the size of CubeSats and according to the CubeSat Design Specification are [[Scalability|scalable]] along only one axis to fit the forms of 0.5U, 1U, 1.5U, 2U, or 3U. All the standard sizes of CubeSat have been built and launched, and represent the form factors for nearly all launched CubeSats as of 2015.<ref>{{Cite web| title = CubeSat| url = http://space.skyrocket.de/doc_sat/cubesat.htm| website = space.skyrocket.de| access-date = 2015-10-18}}</ref> Materials used in the structure must feature the same [[coefficient of thermal expansion]] as the deployer to prevent jamming. Specifically, allowed materials are four aluminum alloys: [[7075 aluminium alloy|7075]], [[6061 aluminium alloy|6061]], [[5005 aluminium alloy|5005]], and [[5052 aluminium alloy|5052]]. Aluminum used on the structure which contacts the P-POD must be [[anodize]]d to prevent [[cold welding]], and other materials may be used for the structure if a waiver is obtained.<ref name='specs'/> Beyond cold welding, further consideration is put into material selection as not all materials can be [[Materials for use in vacuum|used in vacuums]]. Structures often feature soft dampers at each end, typically made of rubber, to lessen the effects of impacting other CubeSats in the P-POD.

Protrusions beyond the maximum dimensions are allowed by the standard specification, to a maximum of {{cvt|6.5|mm}} beyond each side. Any protrusions may not interfere with the deployment rails and are typically occupied by antennas and solar panels. In Revision 13 of the CubeSat Design Specification an extra available volume was defined for use on 3U projects. The additional volume is made possible by space typically wasted in the P-POD Mk III's spring mechanism. 3U CubeSats which utilize the space are designated 3U+ and may place components in a cylindrical volume centered on one end of the CubeSat. The cylindrical space has a maximum diameter of {{cvt|6.4|cm}} and a height no greater than {{cvt|3.6|cm}} while not allowing for any increase in mass beyond the 3U's maximum of {{cvt|4|kg}}. Propulsion systems and antennas are the most common components that might require the additional volume, though the payload sometimes extends into this volume. Deviations from the dimension and mass requirements can be waived following application and negotiation with the [[launch service provider]].<ref name='specs'/>

CubeSat structures do not have all the same strength concerns as larger satellites do, as they have the added benefit of the deployer supporting them structurally during launch.<ref>{{Cite journal |last=Thomas |first=Daniel |date=2021-11-01 |title=Enhancing the electrical and mechanical properties of graphene nanoplatelet composites for 3D printed microsatellite structures |url=https://www.sciencedirect.com/science/article/pii/S2214860421003754 |journal=Additive Manufacturing |volume=47 |pages=102215 |doi=10.1016/j.addma.2021.102215 |issn=2214-8604|url-access=subscription }}</ref> Still, some CubeSats will undergo [[Structural dynamics|vibration analysis]] or [[structural analysis]] to ensure that components unsupported by the P-POD remain structurally sound throughout the launch.<ref>{{Cite journal| title = Stress and Thermal Analysis of CubeSat Structure | journal = Applied Mechanics and Materials| pages = 426–430| volume = 554| doi = 10.4028/www.scientific.net/amm.554.426| first1 = Nur| last1 = Athirah| first2 = Mohd| last2 = Afendi| first3 = Ku| last3 = Hafizan| first4 = N.A.M.| last4 = Amin| first5 = M.S. Abdul| last5 = Majid|year = 2014| s2cid = 110559952}}</ref> Despite rarely undergoing the analysis that larger satellites do, CubeSats rarely fail due to mechanical issues.<ref>{{Cite journal| url=http://web.csulb.edu/~hill/ee400d/Project%20Folder/CubeSat/The%20First%20One%20Hundred%20Cubesats.pdf| title=The First One Hundred CubeSats: A Statistical Look| last=Swartwout| first=Michael| date=December 2013| journal=Journal of Small Satellites| volume=2| issue=2| pages=213| bibcode=2013JSSat...2..213S| access-date=28 November 2015| archive-date=8 December 2015| archive-url=https://web.archive.org/web/20151208093346/http://web.csulb.edu/~hill/ee400d/Project%20Folder/CubeSat/The%20First%20One%20Hundred%20Cubesats.pdf| url-status=dead}}</ref>

===Computing===
Like larger satellites, CubeSats often feature multiple computers handling different tasks in [[Parallel computing|parallel]] including the [[Spacecraft attitude control|attitude control]] (orientation), power management, payload operation, and primary control tasks. COTS attitude-control systems typically include their own computer, as do the power management systems. Payloads must be able to interface with the primary computer to be useful, which sometimes requires the use of another small computer. This may be due to limitations in the primary computer's ability to control the payload with limited communication protocols, to prevent overloading the primary computer with raw data handling, or to ensure payload's operation continues uninterrupted by the spacecraft's other computing needs such as communication. Still, the primary computer may be used for payload related tasks, which might include [[image processing]], [[data analysis]], and [[data compression]]. Tasks which the primary computer typically handles include the delegation of tasks to the other computers, attitude control, calculations for [[orbital maneuver]]s, [[Scheduling (computing)|scheduling]], and activation of active thermal control components. CubeSat computers are highly susceptible to radiation and builders will take special steps to ensure proper operation in the high radiation of space, such as the use of [[ECC memory|ECC RAM]]. Some satellites may incorporate [[Redundancy (engineering)|redundancy]] by implementing multiple primary computers; this could be done on valuable missions to lessen the risk of mission failure. Consumer [[smartphone]]s have been used for computing in some CubeSats, such as NASA's [[PhoneSat]]s.

===Attitude control===
[[File:Near Earth Asteroid Scout.jpg|thumb|[[Near-Earth Asteroid Scout]] concept: a controllable [[solar sail]] CubeSat]]
[[Spacecraft attitude control|Attitude control]] (orientation) for CubeSats relies on miniaturizing technology without significant performance degradation. Tumbling typically occurs as soon as a CubeSat is deployed, due to asymmetric deployment forces and bumping with other CubeSats. Some CubeSats operate normally while tumbling, but those that require pointing in a certain direction or cannot operate safely while spinning, must be detumbled. Systems that perform attitude determination and control include [[reaction wheel]]s, [[magnetorquer]]s, thrusters, [[star tracker]]s, [[Sun sensor]]s, Earth sensors, [[angular rate sensor]]s, and [[GPS navigation device|GPS receivers and antennas]]. Combinations of these systems are typically seen in order to take each method's advantages and mitigate their shortcomings. [[Reaction wheels]] are commonly utilized for their ability to impart relatively large [[Moment (physics)|moments]] for any given energy input, but reaction wheel's utility is limited due to saturation, the point at which a wheel cannot spin faster. Examples of CubeSat reaction wheels include the Maryland Aerospace MAI-101<ref>{{Cite web| url = http://maiaero.com/products/s/mai-101/| title = Maryland Aerospace Reaction Wheels| access-date = September 4, 2015| url-status = dead| archive-url = https://web.archive.org/web/20150716161428/http://maiaero.com/products/s/mai-101/| archive-date = July 16, 2015}}</ref> and the Sinclair Interplanetary RW-0.03-4.<ref>{{Cite web| url = http://www.sinclairinterplanetary.com/reactionwheels| title = Sinclair Interplanetary Reaction Wheels| access-date = September 4, 2015| archive-date = September 24, 2015| archive-url = https://web.archive.org/web/20150924101944/http://www.sinclairinterplanetary.com/reactionwheels| url-status = dead}}</ref> Reaction wheels can be desaturated with the use of thrusters or magnetorquers. Thrusters can provide large moments by imparting a [[Couple (mechanics)|couple]] on the spacecraft but inefficiencies in small propulsion systems cause thrusters to run out of fuel rapidly. Commonly found on nearly all CubeSats are magnetorquers which run electricity through a coil to take advantage of Earth's magnetic field to produce a [[Moment (physics)|turning moment]]. Attitude-control modules and solar panels typically feature built-in magnetorquers. For CubeSats that only need to detumble, no attitude determination method beyond an [[angular rate sensor]] or electronic [[gyroscope]] is necessary.

Pointing in a specific direction is necessary for Earth observation, orbital maneuvers, maximizing solar power, and some scientific instruments. Directional pointing accuracy can be achieved by sensing Earth and its horizon, the Sun, or specific stars. Sinclair Interplanetary's SS-411 Sun sensor<ref>{{Cite web| url = http://www.sinclairinterplanetary.com/digitalsunsensors| title = Sinclair Interplanetary Sun Sensors| access-date = September 4, 2015| archive-date = November 17, 2015| archive-url = https://web.archive.org/web/20151117032733/http://www.sinclairinterplanetary.com/digitalsunsensors| url-status = dead}}</ref> and ST-16 star tracker<ref>{{Cite web| url = http://www.sinclairinterplanetary.com/startrackers| title = Sinclair Interplanetary Star Trackers| access-date = September 4, 2015| archive-date = September 24, 2015| archive-url = https://web.archive.org/web/20150924101946/http://www.sinclairinterplanetary.com/startrackers| url-status = dead}}</ref> both have applications for CubeSats and have flight heritage. Pumpkin's Colony I Bus uses an aerodynamic wing for passive attitude stabilization.<ref>{{Cite web| url = http://www.cubesatkit.com/docs/press/Pumpkin_GAINSTAM_2009.pdf| title = Pumkin's Colony I CubeSat Bus| date = 4 Nov 2009| access-date = September 4, 2015| last = Kalman| first = Andrew}}</ref> Determination of a CubeSat's location can be done through the use of on-board GPS, which is relatively expensive for a CubeSat, or by relaying radar tracking data to the craft from Earth-based tracking systems.

=== Propulsion ===
CubeSat propulsion has made rapid advancements in: [[Cold gas thruster|cold gas]], [[Rocket engine|chemical propulsion]], [[Electrically powered spacecraft propulsion|electric propulsion]], and [[solar sail]]s. The biggest challenge with CubeSat propulsion is preventing risk to the launch vehicle and its primary [[payload]] while still providing significant capability.<ref>{{Cite web| url = https://www.nasa.gov/sites/default/files/files/Small_Spacecraft_Technology_State_of_the_Art_2014.pdf| title = Small Spacecraft Technology State of the Art| date = February 2014| access-date = September 4, 2015| website = NASA| publisher = NASA Ames| last = Frost| first = Chad| url-status = dead| archive-url = https://web.archive.org/web/20150226081748/http://www.nasa.gov/sites/default/files/files/Small_Spacecraft_Technology_State_of_the_Art_2014.pdf| archive-date = February 26, 2015}}</ref> Components and methods that are commonly used in larger satellites are disallowed or limited, and the CubeSat Design Specification (CDS) requires a waiver for pressurization above {{cvt|1.2|atm}}, over 100 Wh of stored chemical energy, and hazardous materials.<ref name='specs'/> Those restrictions pose great challenges for CubeSat propulsion systems, as typical space propulsion systems utilize combinations of high pressures, high energy densities, and hazardous materials. Beyond the restrictions set forth by [[launch service provider]]s, various technical challenges further reduce the usefulness of CubeSat propulsion. [[Gimbaled thrust]] cannot be used in small engines due to the complexity of gimbaling mechanisms, thrust vectoring must instead be achieved by thrusting asymmetrically in multiple-nozzle propulsion systems or by changing the center of mass relative to the CubeSat's geometry with actuated components.<ref>{{Cite web| title = PowerCube| url = http://www.tethers.com/PowerCube.html| website = www.tethers.com| access-date = 2015-11-26}}</ref> Small motors may also not have room for [[Throttle|throttling]] methods that allow smaller than fully on thrust, which is important for precision maneuvers such as [[Space rendezvous|rendezvous]].<ref>{{Cite book| chapter = Liquid-Propellant Rocket Engine Throttling: A Comprehensive Review| publisher = American Institute of Aeronautics and Astronautics| doi = 10.2514/6.2009-5135| first1 = Matthew| last1 = Casiano| first2 = James| last2 = Hulka|author3-link=Vigor Yang| first3 = Vigor| last3 = Yang| title = 45th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit| year = 2009| isbn = 978-1-60086-972-3| hdl = 2060/20090037061| s2cid = 111415930}}</ref> CubeSats which require longer life also benefit from propulsion systems; when used for [[Orbital station-keeping|orbit keeping]] a propulsion system can slow [[orbital decay]].

==== Cold gas thrusters ====
A [[cold gas thruster]] typically stores [[inert gas]], such as [[nitrogen]], in a [[Pressure vessel|pressurized tank]] and releases the gas through a [[Rocket engine nozzle|nozzle]] to produce thrust. Operation is handled by just a single [[valve]] in most systems, which makes cold gas the simplest useful propulsion technology.<ref name=":1">{{Cite web|title=Spacecraft Propulsion – Chemical |url=http://www.sv.vt.edu/classes/ESM4714/Student_Proj/class03/stillwater/prj/background/sp_chemical.htm| website=www.sv.vt.edu| access-date=2015-11-26| archive-url=https://web.archive.org/web/20151004075951/http://www.sv.vt.edu/classes/ESM4714/Student_Proj/class03/stillwater/prj/background/sp_chemical.htm| archive-date=2015-10-04| url-status=dead}}</ref> Cold gas propulsion systems can be very safe since the gases used do not have to be volatile or [[Corrosive substance|corrosive]], though some systems opt to feature dangerous gases such as [[sulfur dioxide]].<ref>{{Cite web| title=Propulsion Unit for Cubesats (PUC)| url=http://www.cuaerospace.com/Products/SmallSatellitePropulsion/TabId/195/ArtMID/737/ArticleID/169/Propulsion-for-Cubesats-PUC-%E2%80%93-A-Smart-Robust-Propulsion-System-for-CubeSats.aspx| access-date=26 Nov 2015| publisher=CU Aerospace, LLC}}</ref> This ability to use inert gases is highly advantageous to CubeSats as they are usually restricted from hazardous materials. Only low performance can be achieved with them,<ref name=":1" /> preventing high impulse maneuvers even in low mass CubeSats. Due to this low performance, their use in CubeSats for main propulsion is limited and designers choose higher efficiency systems with only minor increases in complexity. Cold gas systems more often see use in CubeSat attitude control.

==== Chemical propulsion ====
[[Rocket engine|Chemical propulsion]] systems use a chemical reaction to produce a high-pressure, high-temperature gas that accelerates out of a [[Propelling nozzle|nozzle]]. Chemical propellant can be liquid, solid or a hybrid of both. Liquid propellants can be a [[Monopropellant rocket|monopropellant]] passed through a [[catalyst]], or [[Liquid-propellant rocket|bipropellant]] which [[Combustion|combusts]] an [[Oxidizing agent|oxidizer]] and a [[fuel]]. The benefits of [[Monopropellant rocket|monopropellants]] are relatively low-complexity/high-thrust output, low power requirements, and high reliability. Monopropellant motors tend to have high thrust while remaining comparatively simple, which also provides high reliability. These motors are practical for CubeSats due to their low power requirements and because their simplicity allows them to be very small. Small [[hydrazine]] fueled motors have been developed,<ref name=":0">{{Cite web| url=http://www.rocket.com/cubesat| title=Aerojet CubeSat Thrusters| access-date=September 4, 2015| website=Aerojet Rocketdyne| archive-url=https://web.archive.org/web/20150823030523/http://www.rocket.com/cubesat| archive-date=August 23, 2015| url-status=dead}}</ref> but may require a waiver to fly due to restrictions on hazardous chemicals set forth in the CubeSat Design Specification.<ref name="specs" /> Safer chemical propellants which would not require hazardous chemical waivers are being developed, such as AF-M315 ([[hydroxylammonium nitrate]]) for which motors are being or have been designed.<ref name=":0" /><ref>{{Cite web |url=http://busek.com/technologies__greenmonoprop.htm |title=Busek Green monopropellant thruster |access-date=September 4, 2015 |website=Busek Space Propulsion |publisher=Busek}}</ref> A "Water Electrolysis Thruster" is technically a chemical propulsion system, as it burns [[hydrogen]] and [[oxygen]] which it generates by on-orbit [[electrolysis of water]].<ref name="Tethers2015">{{cite web |url=http://www.tethers.com/HYDROS.html |title=HYDROS – Water Electrolysis Thruster |work=Tethers Unlimited, Inc. |date=2015 |access-date=2015-06-10}}</ref>

==== Electric propulsion ====
[[File:BIT-3 Iodine 60W with BHC-50E.jpg|thumb|The [[Busek]] BIT-3 [[gridded ion thruster]] will be used to propel the [[Lunar IceCube]] 6U CubeSat.]]
CubeSat [[Electrically powered spacecraft propulsion|electric propulsion]] typically uses electric energy to accelerate propellant to high speed, which results in high [[specific impulse]]. Many of these technologies can be made small enough for use in nanosatellites, and several methods are in development. Types of electric propulsion currently being designed for use in CubeSats include [[Hall-effect thruster]]s,<ref>{{Cite web| title = Busek Hall Effect Thrusters| url = http://www.busek.com/technologies__hall.htm| website = www.busek.com| access-date = 2015-11-27}}</ref> [[ion thruster]]s,<ref>{{Cite web| title = Busek Ion Thrusters| url = http://www.busek.com/technologies__ion.htm| website = www.busek.com| access-date = 2015-11-27}}</ref> [[pulsed plasma thruster]]s,<ref>{{Cite web| title = PPTCUP| url = http://www.mars-space.co.uk/projects/pptcup| website = www.mars-space.co.uk| access-date = 2015-11-27| archive-url = https://web.archive.org/web/20151208051408/http://www.mars-space.co.uk/projects/pptcup| archive-date = 2015-12-08| url-status = dead}}</ref> [[Colloid thruster|electrospray thrusters]],<ref>{{Cite web|title = Busek Electrospray Thrusters| url = http://www.busek.com/technologies__espray.htm| website = www.busek.com| access-date = 2015-11-27}}</ref> and [[Resistojet rocket|resistojets]].<ref>{{Cite web| title = Busek Electrothermal Thrusters| url = http://www.busek.com/technologies__therm.htm| website = www.busek.com| access-date = 2015-11-27| archive-date = 2015-12-08| archive-url = https://web.archive.org/web/20151208055749/http://www.busek.com/technologies__therm.htm| url-status = dead}}</ref> Several notable CubeSat missions plan to use electric propulsion, such as NASA's [[Lunar IceCube]].<ref name="LunarIceCube2015">{{cite web |url=http://www.nasa.gov/feature/goddard/lunar-icecube-to-take-on-big-mission-from-small-package |title=Lunar IceCube to Take on Big Mission from Small Package |work=NASA |date=2015 |access-date=2015-09-01 }}</ref> The high efficiency associated with electric propulsion could allow CubeSats to propel themselves to Mars.<ref name="Mars2015">{{cite news |url=http://www.thespacereview.com/article/2506/1 |title=Mars missions on the cheap |work=The Space Review |location=USA |date=5 May 2014 |access-date=2015-05-21 }}</ref> Electric propulsion systems are disadvantaged in their use of power, which requires the CubeSat to have larger solar cells, more complicated power distribution, and often larger batteries. Furthermore, many electric propulsion methods may still require pressurized tanks to store propellant, which is restricted by the CubeSat Design Specification.

The [[ESTCube-1]] used an [[Electric sail|electric solar-wind sail]], which relies on an electromagnetic field to act as a sail instead of a solid material. This technology used an [[electric field]] to deflect [[protons]] from [[solar wind]] to produce thrust. It is similar to an [[electrodynamic tether]] in that the craft only needs to supply electricity to operate.

==== Solar sail ====
[[Solar sail]]s&nbsp;(also called&nbsp;light sails&nbsp;or&nbsp;photon sails) are a form of&nbsp;spacecraft propulsion&nbsp;using the&nbsp;[[radiation pressure]]&nbsp;(also called solar pressure) from stars to push large ultra-thin mirrors to high speeds, requiring no propellant. Force from a solar sail scales with the sail's area, this makes sails well suited for use in CubeSats as their small mass results in the greater acceleration for a given solar sail's area. However, solar sails still need to be quite large compared to the satellite, which means useful solar sails must be  deployed, adding mechanical complexity and a potential source of failure. This propulsion method is the only one not plagued with restrictions set by the CubeSat Design Specification, as it does not require high pressures, hazardous materials, or significant chemical energy. A small number of CubeSats have employed a solar sail as its main propulsion and stability in deep space, including the 3U [[NanoSail-D2]] launched in 2010, and the [[LightSail-1]] in May 2015.

[[LightSail-2]] successfully deployed on a Falcon Heavy rocket in 2019,<ref name="Name change">{{cite news |last=Davis |first=Jason |url=http://www.planetary.org/blogs/jason-davis/2016/20160229-meet-lightsail-2.html |title=Meet LightSail 2, The Planetary Society's new solar sailing CubeSat |work=The Planetary Society |date=1 March 2016 |access-date=2016-03-01}}</ref><ref>{{Cite web |url=https://www.planetary.org/blogs/jason-davis/lightsail-2-successful-flight-by-light.html |title=LightSail 2 Spacecraft Successfully Demonstrates Flight by Light |website=www.planetary.org |access-date=2020-02-29}}</ref> while one CubeSat that was planned to launch on the [[Space Launch System]]'s first flight ([[Artemis 1]]) in November 2022 was set to use a solar sail: the [[Near-Earth Asteroid Scout]] (NEA Scout).<ref name="McNutt">{{cite web |last1=McNutt |first1=Leslie |last2=Castillo-Rogez |first2=Julie |date=2014 |title=Near-Earth Asteroid Scout |url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20140012882.pdf |access-date=2015-05-13 |work=NASA |publisher=American Institute of Aeronautics and Astronautics}}</ref> The CubeSat was declared lost when communications were not established within 2 days.<ref>{{Cite web |last=Dickinson |first=David |date=2022-12-06 |title=Status Update: Artemis 1's SmallSat Missions |url=https://skyandtelescope.org/astronomy-news/status-update-artemis-1s-smallsat-missions/ |access-date=2023-04-23 |website=Sky&Telescope}}</ref>

===Power===
[[File:Winglet Pumpkin Solar Pannels for CubeSat.png|thumb|Winglet solar panels increase surface area for power generation.]]
CubeSats use [[solar cell]]s to convert solar light to electricity that is then stored in rechargeable [[Lithium-ion battery|lithium-ion batteries]] that provide power during eclipse as well as during peak load times.<ref>{{cite web |url=http://www.diyspaceexploration.com/power-system-budget-analysis/ |title=CubeSats: Power System and Budget Analysis |work=DIY Space Exploration |date=2015 |access-date=2015-05-22 |url-status=usurped |archive-url=https://web.archive.org/web/20150522113355/http://www.diyspaceexploration.com/power-system-budget-analysis/ |archive-date=2015-05-22 }}</ref> These satellites have a limited surface area on their external walls for solar cells assembly, and has to be effectively shared with other parts, such as antennas, optical sensors, camera lens, propulsion systems, and access ports. Lithium-ion batteries feature high energy-to-mass ratios, making them well suited to use on mass-restricted spacecraft. Battery charging and discharging is typically handled by a dedicated electrical power system (EPS). Batteries sometimes feature heaters<ref>{{Cite web| title = Batteries|url = http://cubesatcookbook.com/directory/batteries/ |website = The CubeSat Cookbook|date = 9 March 2010 | access-date = 2015-10-20}}</ref> to prevent the battery from reaching dangerously low temperatures which might cause battery and mission failure.<ref>{{Cite web|title = Lithium Battery Failures| url = http://www.mpoweruk.com/lithium_failures.htm| website = www.mpoweruk.com| access-date = 2015-10-20}}</ref>

The rate at which the batteries decay depends on the number of cycles for which they are charged and discharged, as well as the depth of each discharge: the greater the average depth of discharge, the faster a battery degrades. For LEO missions, the number of cycles of discharge can be expected to be on the order of several hundred.

Due to size and weight constraints, common CubeSats flying in LEO with body-mounted solar panels have generated less than 10 W.<ref>{{Cite journal|last1=Spangelo|first1=Sara|last2=Longmier|first2=Benjamin|date=2015-04-20|title=Optimization of CubeSat System-Level Design and Propulsion Systems for Earth-Escape Missions|journal=Journal of Spacecraft and Rockets|volume=52|issue=4|pages=1009–1020|doi=10.2514/1.A33136|bibcode=2015JSpRo..52.1009S|issn=0022-4650|hdl=2027.42/140416|url=https://deepblue.lib.umich.edu/bitstream/2027.42/140416/1/1.A33136.pdf|hdl-access=free}}</ref> Missions with higher power requirements can make use of [[Spacecraft attitude control|attitude control]] to ensure the solar panels remain in their most effective orientation toward the Sun, and further power needs can be met through the addition and orientation of deployable solar arrays, which can be unfolded to a substantially larger area on-orbit. Recent innovations include additional spring-loaded solar arrays that deploy as soon as the satellite is released, as well as arrays that feature [[thermal knife]] mechanisms that would deploy the panels when commanded. CubeSats may not be powered between launch and deployment, and must feature a [[remove before flight|remove-before-flight]] pin which cuts all power to prevent operation during loading into the P-POD. Additionally, a deployment switch is actuated while the craft is loaded into a P-POD, cutting power to the spacecraft and is deactivated after exiting the P-POD.<ref name="specs" />

===Telecommunications===
[[File:Secondary antennas4.gif|thumb|upright=0.8|Deployable high-gain mesh reflector antenna operating at Ka-band (27–40 GHz) for the radar in a CubeSat ([[RaInCube]])]]
The low cost of CubeSats has enabled unprecedented access to space for smaller institutions and organizations but, for most CubeSat forms, the range and available power is limited to about 2&nbsp;W for its communications antennae.<ref name="Grumman2014">{{cite news|last=Ochoa|first=Daniel |url=http://www.northropgrumman.com/BusinessVentures/AstroAerospace/Documents/pageDocs/tech_papers/SmallSat_DeployableHelical_ochoa_SSC14-IX-4.pdf |title=Deployable Helical Antenna for Nano-Satellite |work=Northrop Grumman Aerospace Systems |date=2014 |access-date=2015-05-21 |archive-date=2016-05-13 |archive-url=https://web.archive.org/web/20160513193738/http://www.northropgrumman.com/BusinessVentures/AstroAerospace/Documents/pageDocs/tech_papers/SmallSat_DeployableHelical_ochoa_SSC14-IX-4.pdf |url-status=dead }}</ref>

Because of tumbling and low power range, radio-communications are a challenge. Many CubeSats use an [[omnidirectional antenna|omnidirectional]] [[monopole antenna|monopole]] or [[dipole antenna]] built with commercial measuring tape. For more demanding needs, some companies offer [[high-gain antenna]]e for CubeSats, but their deployment and pointing systems are significantly more complex.<ref name="Grumman2014"/> For example, [[Massachusetts Institute of Technology|MIT]] and [[Jet Propulsion Laboratory|JPL]] are developing an inflatable dish antenna based on a [[mylar]] skin inflated with a [[sublimation (phase transition)|sublimating powder]], claiming a 7× boost in range—potentially able to reach the Moon—but questions linger concerning survivability after micrometeor impacts.<ref name="InflatableDish">{{cite news |last=Chu |first=Jennifer |url=http://newsoffice.mit.edu/2013/inflatable-antennae-could-give-cubesats-greater-reach-0906 |title=Inflatable antennae could give CubeSats greater reach |work=MIT News |location=USA |date=6 September 2015 |access-date=2015-05-21 }}</ref> JPL has successfully developed [[X band|X-band]] and [[Ka band|Ka-band]] high-gain antennas for [[Mars Cube One|MarCO]]<ref name=":3">{{Cite book |last1=Hodges |first1=R. E. |last2=Chahat |first2=N. E. |last3=Hoppe |first3=D. J. |last4=Vacchione |first4=J. D. |title=2016 IEEE International Symposium on Antennas and Propagation (APSURSI) |chapter=The Mars Cube One deployable high gain antenna |date=2016-06-01 |pages=1533–1534 |doi=10.1109/APS.2016.7696473 |isbn=978-1-5090-2886-3 |s2cid=27368017}}</ref><ref name=":4">{{Cite web |url=http://hackaday.com/2017/02/22/interview-nacer-chahat-designs-antennae-for-mars-cubesats/|title=Dr. Nacer Chahat Interview on High-gain deployable antennas for CubeSats|last=Chahat|first=Nacer|date=2017-02-22|website=Hackaday}}</ref> and Radar in a CubeSat ([[RaInCube]]) missions.<ref name=":4"/><ref>{{Cite journal |last1=Chahat |first1=N. |last2=Hodges |first2=R. E. |last3=Sauder |first3=J. |last4=Thomson |first4=M. |last5=Peral |first5=E. |last6=Rahmat-Samii |first6=Y. |date=2016-06-01 |title=CubeSat Deployable Ka-Band Mesh Reflector Antenna Development for Earth Science Missions |journal=IEEE Transactions on Antennas and Propagation |volume=64 |issue=6 |pages=2083–2093 |doi=10.1109/TAP.2016.2546306 |issn=0018-926X |bibcode=2016ITAP...64.2083C |s2cid=31730643}}</ref><ref>{{Cite web |url=http://www.jpl.nasa.gov/news/news.php?feature=6672|title=A Box of 'Black Magic' to Study Earth from Space |website=NASA/JPL |access-date=2017-01-22}}</ref>

==== Antennas ====
Traditionally, [[Low Earth orbit|Low Earth Orbit]] Cubesats use antennas for communication purpose at UHF and S-band. To venture farther in the [[Solar System]], larger antennas compatible with the [[NASA Deep Space Network|Deep Space Network]] (X-band and Ka-band) are required. [[Jet Propulsion Laboratory|JPL]]'s engineers developed several deployable high-gain antennas compatible with 6U-class CubeSats<ref>{{cite book |last=Chahat |first=Nacer |editor-first1=Nacer |editor-last1=Chahat |author-link= |date= 13 December 2020 |title=CubeSat Antenna Design |url= https://onlinelibrary.wiley.com/doi/book/10.1002/9781119692720 |location= |publisher=Wiley |page= |doi=10.1002/9781119692720 |isbn= 9781119692584 |s2cid=242921969 }}</ref> for MarCO<ref name=":3" /><ref name=":5">{{Cite web|url=http://hackaday.com/2017/02/22/interview-nacer-chahat-designs-antennae-for-mars-cubesats/|title=Interview: Nacer Chahat Designs Antennas for Mars CubeSats|last=By|website=Hackaday|access-date=2017-02-25|date=2017-02-22}}</ref> and [[Near-Earth Asteroid Scout]].<ref>{{Cite web|url=https://www.nasa.gov/content/nea-scout|title=NEA Scout mission|date=2015-10-30|website=NASA.gov}}</ref> JPL's engineers have also developed a {{cvt|0.5|m}} mesh reflector antenna operating at Ka-band and compatible with the DSN<ref name=":3" /><ref name=":5" /><ref>{{Cite journal|last1=Chahat|first1=N.|last2=Hodges|first2=R. E.|last3=Sauder|first3=J.|last4=Thomson|first4=M.|last5=Rahmat-Samii|first5=Y.|date=2017-01-01|title=Deep Space Network Telecommunication CubeSat Antenna: Using the deployable Ka-band mesh reflector antenna.|journal=IEEE Antennas and Propagation Magazine|volume=PP|issue=99|pages=31–38|doi=10.1109/MAP.2017.2655576|issn=1045-9243|bibcode=2017IAPM...59...31C|s2cid=25220479}}</ref> that folds in a 1.5U stowage volume. For MarCO, JPL's antenna engineers designed a Folded Panel Reflectarray (FPR)<ref>{{Cite journal|last1=Hodges|first1=R. E.|last2=Chahat|first2=N.|last3=Hoppe|first3=D. J.|last4=Vacchione|first4=J. D.|date=2017-01-01|title=A Deployable High-Gain Antenna Bound for Mars: Developing a new folded-panel reflectarray for the first CubeSat mission to Mars.|journal=IEEE Antennas and Propagation Magazine|volume=PP|issue=99|pages=39–49|doi=10.1109/MAP.2017.2655561|issn=1045-9243|bibcode=2017IAPM...59...39H|s2cid=35388830}}</ref> to fit on a 6U CubeSat bus and supports X-band Mars-to-Earth telecommunications at 8&nbsp;kbit/s at 1AU.

=== Thermal management ===
Different CubeSat components possess different acceptable temperature ranges, beyond which they may become temporarily or permanently inoperable. Satellites in orbit are heated by [[Thermal radiation|radiative heat]] emitted from the [[Sun]] directly and reflected off Earth, as well as heat generated by the craft's components. CubeSats must also [[Radiative cooling|cool by radiating heat]] either into space or into the cooler Earth's surface, if it is cooler than the spacecraft. All of these radiative heat sources and sinks are rather constant and very predictable, so long as the CubeSat's orbit and eclipse time are known.

Components used to ensure the temperature requirements are met in CubeSats include [[multi-layer insulation]] and [[Heating element|heaters]] for the battery. Other [[spacecraft thermal control]] techniques in small satellites include specific component placement based on expected thermal output of those components and, rarely, deployed thermal devices such as [[louver]]s. Analysis and simulation of the spacecraft's thermal model is an important determining factor in applying thermal management components and techniques. CubeSats with special thermal concerns, often associated with certain deployment mechanisms and payloads, may be tested in a [[thermal vacuum chamber]] before launch. Such testing provides a larger degree of assurance than full-sized satellites can receive, since CubeSats are small enough to fit inside of a thermal vacuum chamber in their entirety. [[Thermometer|Temperature sensor]]s are typically placed on different CubeSat components so that action may be taken to avoid dangerous temperature ranges, such as reorienting the craft in order to avoid or introduce direct thermal radiation to a specific part, thereby allowing it to cool or heat.

===Costs===
CubeSat forms a cost-effective independent means of getting a payload into orbit.<ref name="tiny"/> After delays from low-cost launchers such as [[Interorbital Systems]],<ref>As noted in the linked article, Interorbital promised its Neptune 45 – intended to carry ten CubeSats, among other cargo – would launch in 2011, but as of 2014 it had yet to do so.</ref> launch prices have been about $100,000 per unit,<ref>{{cite web | title = OSSI-1 Amateur Radio CubeSat launched | url = http://www.southgatearc.org/news/april2013/ossi_1_amateur_radio_cubesat_launched.htm | year = 2013 | publisher = Southgate Amateur Radio News | access-date = 2014-07-07 | archive-url = https://web.archive.org/web/20150924104046/http://www.southgatearc.org/news/april2013/ossi_1_amateur_radio_cubesat_launched.htm | archive-date = 2015-09-24 | url-status = dead }}</ref><ref>{{Cite web|title = Commercial Space Launch Schedule and Pricing|url = http://www.spaceflightindustries.com/schedule-pricing/|website = Spaceflight|access-date = 2015-10-18|url-status = dead|archive-url = https://web.archive.org/web/20151016001943/http://www.spaceflightindustries.com/schedule-pricing/|archive-date = 2015-10-16}}</ref> but newer operators are offering lower  pricing.<ref>[https://rocketlabusa.com/space-is-open-for-business-online/ "Space Is Open For Business, Online"], rocketlabusa.com</ref> A typical price to launch a 1U cubesat with a full service contract (including end-to-end integration, licensing, transportation etc.) was about $60,000 in 2021.

Some CubeSats have complicated components or instruments, such as [[LightSail-1]], that push their construction cost into the millions of dollars,<ref>{{Cite web| title = After letdown, solar-sail project rises again| url = http://www.nbcnews.com/id/33812469/ns/technology_and_science-space/#.ViPAwitRKVI| archive-url = https://web.archive.org/web/20150518095341/http://www.nbcnews.com/id/33812469/ns/technology_and_science-space/#.ViPAwitRKVI| url-status = dead| archive-date = May 18, 2015| website = msnbc.com| access-date = 2015-10-18| date = 2009-11-10}}</ref> but a basic 1U CubeSat can cost about $50,000 to construct.<ref>{{Cite web| title = Cubesats explained and why you should build one| url = http://www.diyspaceexploration.com/what-are-cubesats/| website = DIY Space Exploration| access-date = 2015-10-18| url-status = usurped| archive-url = https://web.archive.org/web/20151013051317/http://www.diyspaceexploration.com/what-are-cubesats| archive-date = 2015-10-13}}</ref> This makes CubeSats a viable option for some schools, universities, and small businesses.